Inflammatory bowel disease (IBD) is one of the most prevalent gastrointestinal disease burdens in the US, with an overall health care cost of more than $1.7 billion and affecting an estimate of 1.4 million patients in the US. Crohn's disease (CD) and ulcerative colitis (UC) are the two major types of inflammatory bowel disease (IBD), both characterized by chronic and relapsing inflammation in the intestinal tract which commonly requires a lifetime of care. Meanwhile, infants with microvillus inclusion disease (MVID) have severe malabsorption caused by hypoplasia and/or atrophy of the intestinal epithelium. These infants require total parental nutrition to survive but quickly develop liver failure and potential death within 2 years. The only effective therapeutic approach is small intestine transplantation that requires a donor and is logistically complicated and impractical. One potential long term treatment for IBD and MVID would be therapeutic intestinal stem cell (ISC) transplantation. The goal of this renewal grant is to use our biodegradable and biocompatible elastomers as a multifunctional delivery platform for drug and cell delivery to treat diseases affecting intestinal mucosa. Although ISCs could be delivered and engraft to intestinal epithelium, initial cell retention with high efficiency is not easily achieved owing to the harsh intestinal environment and the lack of supportive stem cell niche prior to engraftment. Through combining biodegradable elastomers with our high efficiency ISC expansion protocols, we can deliver stem cells under the protection of a defined synthetic niche. By maximizing rapid adhesion and engraftment, we aim to achieve high efficiency delivery of stem cells to diseased epithelium. We propose to utilize the delivery platform either as small cell/drug carriers, which can disperse quickly into the colon via enema for Ulcerative Colitis, or as larger patches that will be delivere via endoscope for Crohn's disease or intestinal anastomotic failure. These delivery vehicles will achieve 1. Efficient and selective adhesion to damaged or diseased intestinal epithelium; 2. Survival of delivered stem cells before and during engraftment, and 3. local delivery of anti-inflammatory agents such as IL-10, IL-22, or TNF-? neutralizing antibodies to facilitate and maximize the engraftment of stem cells and maintain remission. We aim to 1. Develop biodegradable and biocompatible elastomer patch enabling efficient and selective mucosal adhesion via both endoscopic (Crohn's disease) and enema-based (ulcerative colitis) delivery in vivo. 2. Engineer elastomer patch to support intestinal stem cell growth while control- releasing anti-inflammatory agents in vitro. 3. Evaluate drug and cell therapeutic efficacy in vivo.